1. Field of the Invention
The present invention is directed to wellbore milling systems and operations in which the interior of a whipstock is milled out. The present invention is also directed to wellbore mills, mill guides, whipstocks, combinations thereof, and methods of their use.
2. Description of Related Art
The prior art discloses a wide variety of apparatuses and methods of their use for re-opening a pathway through a whipstock set in a wellbore. Such a whipstock or diverter may block the wellbore in which it is set and re-opening of the wellbore requires removal of the whipstock or the creation of a pathway through it.
A wide variety of U.S. patents present systems with hollow whipstocks and various systems and methods for either whipstock removal or for opening a path through a whipstock.
There has been a need for an efficient and effective system and method for opening a pathway through a whipstock in a wellbore.